Stroboscopic Speed Test Record

Real-time speed control strobe test record. Includes cartridge break-in groove. One side has two sets of (x3) rings - One set for countries operating at 50Hz and another set for countries operating at 60Hz. Each set of rings has a subset for 33⅓/45/78 rpm. The other side has one set of rings for 300Hz, to be used in conjunction with the calibrated Clearaudio 300 Hz quartz light source (Art no. AC 039) There is no recorded music in the grooves....it is intended to calibrate the playing speed with the cartridge in a playing position, factoring in centripetal forces, drag and other friction-related effects (which is not possible for paper-based strobe discs). The grooves are also intended for cartridges to be 'burnt in' over a period of many hours continual playing.